Population Dynamics Flashcards
Population dynamics
- the expansion, decline, or maintenance of populations
- the influence of dispersal on distribution and abundance
- survival and reproduction in populations
Example of dispersal from expanding populations
Africanized bees
Examples of wind dispersals
1) Dandelion seeds
2) waterborne barnacle larvae
3) Juvenile spiders (Garden Spider)
Cohort life table
Data from birth to death on a group of individuals that are born (or germinate) at about the same time; requires checking the cohort repeatedly over years
Static life table
- Records the age at death of a large number of individuals (born at different times)
- Involved either tagging individuals at birth or estimating ages at death
Type I survivorship
Juvenile survival is high and most mortality occurs among older individuals
Type II survivorship
Individuals in the population die at an equal rate regardless of age
Type III survivorship
Individuals die at a high rate as juvenile and then at much lower rates later in life
numerical responses
are changes in the density of predator populations in response to increased prey population.
Spats
flash floods
Drift
downstream movement of stream organisms
Colonization cycle
is a dynamic view of stream populations in which upstream and downstream dispersal have major influences on stream populations
subpopulation
is a part of a larger population with which it sustains a limited exchange of individuals through immigrations and emigrations.
Metapopulation
A discontinuous group of spatially isolated subpopulations that are connected by significant exchange of individuals among patches
ongoing dispersal can join numerous ___populations to form ___populations
sub, meta
